I recently bought it when best buy had it for 39.99
It will make you sweat, but it can't really hold my attention very long.
Some of the games are kind of dumb. I got my bf to play with me because I had seen reviews saying it was not big enough for too people and it was fine, we could both perform the activity on the mat.
I don't have any other wii fitness game to compare it to though, so for $39 I would buy it.